Device for producing noncircular profiles



Aug. 12, 1952 R MUSYL 2,606,403

I DEVICE FOR PRODUCING NONCIRCULAR PROFILES Filed May 4, l949 4 Sheets-Sheet- 1 o boo 00 INVEN TOR:

QUEER T 'MUSVL Arm/a V z- 12, 1952 R. MUSYL 2,606,403

DEVICE FOR PRODUCING NONCIRCULAR PROFILES Filed May 4, 1949 4 Sheets-Sheet 2 figfl L8 Fig.12

IN 5 N TOR:

ROBERT MUSVL A T TORN V Aug. 12, 1952 R. MUSYL 2,606,403

- DEVICE FOR PRODUCING NONCIRCULAR PROFILES Filed May 4, 1949 4 Sheets-Sheet 3 A T TORNE Aug- 12, 19 2 R. MUSYL 2,606,403

DEVICE FOR PRODUCING NONCIRCULAR PROFILES Filed May 4, 1949 4 Shets-Sheet 4 5 g INVENTOR:

. oBERr/wusm ATTOR V Patented Aug. 12, 1952 DEvIoE Eon. rnonucmc n orrcraooma PROFILES Robert Musyl, Vienna, Austria, assignor to Mannfacture lde Machines deflaute Ehin, Moulhause-Burtzwiler, France, a firm of France Application May 4, 1949, Serial No. 91,351 In Austria. May 8, 1948 p 17' Claims.

The presentinvention relates to a device and/or machine-tool capable of precisely producing noncircular cyclic innerand outer-profiles, whereby non- -circular cyclic profiles are, understood in this description to cover mainlyeccentrics, elliptical two-cornered profiles, as well as three-cornered, four-cornered, etc. profiles. These profiles serve chiefly the purpose of Connecting shafts and hubs. The task which the invention intends to solve is to create a machine on which both the preliminary work of turning and milling, and the finishing work of outer-. or inner-grinding can be carried out.

Deviceshave already been known on which non-circular bodies,' e. g. cyclic, three-cornered profiles can be ground inside and outside with the help of cinematic gears. However, these devices are characterized by the peculiarity of periodic alterations of the angular velocity of the workpiece being indispensable during the production of the profile. The periodical accelerations and retardations of the rotating workpiece, occuring in the course of operation, unavoidably, entrain distortions of the profile. In order to keep these distortions Within reasonable limits, the operating speed ofthe workpiece must be reduced to a certain level which constitutes a considerable. drawback of the devices known.

A further disadvantage of the hitherto devices consists in that the whole grinding block participates in the oscillating movement of the tool in respect to the workpiece," necessary for obtaining the non-circular profile. Thereby forces of inertia are generated which reduce the precision of the profile. Besides the finish is impaired by the shocks caused by the driving motor, which participates in the oscillation of the grinding block, being but uncompletely balanced.

Moreover, the devices known do not render possible a preliminary working so that for this purpose separate machines operating. according to other methods must .be employed. Consequently, a considerable andunequalgrinding allowance is indispensable which reduces the economical efficiency oflitheipre'aliminary' work. Fur

thermore, there is the danger of the'finished surfaces showing a dilferent degree of hardness in case of a surface-hardening process being carried out between the preliminary work and the finishing.

With the devices known the control of the osc ll tory movement is taken car of y the sc-ca ed eccentric shaft de rmin the fierence between. the inner-, and t e -c l of the non-circular prOfilQ ZQhQ produced. if,

for each diameter the most favourable shape of profile is to be selected, the eccentricity varies in proportion tothe nominal diameter. However, the machines known are but prQvided with a small number of eccentric units which, owing to their complicated shape, are extremely expensive. Hence, with one eccentricity a wide diameter range must be covered, the result being that within one such range the small diameter profiles aretoo pointed and the large diameter profiles too round.

The transition from one eccentricity to another necessitates the exchange of the eccentricshaft-unit, bound up with complicated manipulations. v

The disadvantages enumerated abovev extraordinarily impair the practical usefulness of the device hither known. I

The device according. to'jthe present invention not only permits to eliminate these drawbacks, but additionally renders possible the production of non-circular profiles'ot any number of corners (multi-corneredprofiles). In the following the ch e feature of the invention are put forth:

(1) According to the invention the oscillating motion is not imparted to the entire tool-block, but solely tofthetool and to the tool-holder. Besides, the cyclic non-circular profile is, in a manner already known, so shaped that it can be producedfwith the workpiece rotating at a uniform speed. By the reductionof the oscillating masses on the one hand, and by the uniform angular velocity of the workpiece on the other hand, the working speed can be increased to a multiple of that of the hitherto known devices without provoking-distortions of the profile.

As according to the invention the tool-block does not participate in' the oscillating motions of the tool, the driving motor too remains stationary, so thatthe quality of the finish is not impaired even if the dynamical balance of the motor is not quite irreproachable.

2) The control motions of the tool are effected according to'fthe invention in such a manner that "bothitsfoscillating movement in the feeding direction andin the direction perpendicular thereto are derived from one sole eccentric,

require a time-absorbing manipulation, but simply the operation of a hand wheel.

(3) The mechanisms taking care of the motions of the oscillating grinding wheel is according to the invention designed in such a manner that the number of the corners of the non-circular profile to be produced can be altered by simply altering the lever transmissions ratio.

(4) The simple design of the tool control renders it possible without difiiculties to control the oscillations of the tools required for the preliminary working of the profile or the profiles in the same manner as the grinding wheels, so as to warrant an equal grinding allowance. These tools may e. g. be so arranged that they are brought into their working position by way of a swivelling motion of the tool-block. Consequently, the same machine can be used both for the preliminary operations of turning and milling, and the finishing operations by insideand outside-grinding without entailing any noteworthy changes on the machine.

In the Figs. 1-12 an embodiment of the invention is represented by way of example. The Figs. 1-3 show various positions of the workpiece in respect to the tool.

Fig. 4 is a diagram representing a gear for driving a grinding Wheel for innerand outer-grinding operations.

Fig. 5 shows the continuously adjustable control eccentric.

The Figs. 6 and 7 are a longitudinal and a transversal section through the drive of the milling device.

Fig. 8 is a frontal view of the whole machinetool. and

Fig. 9 is a lateral view thereto.

Fig. 10 is aview of the machine frame above with the grinding spindle for inside work being located in the operation.

The Figs. 11-12 are a plan and an end view of the machine, when used for milling.

The Figs. 1-3 represent by way of example a non-circular two-cornered workpiece, whereby the method of grinding the outer profile is illustrated in various working positions. The motion of the tool is arranged in such a manner that the operation is always carried out in the perpendicular to the curve, which means that the shape of the profile generated is independent of the diameter of the tool. While the workpiece I executes one revolution the tool 2 is compelled, on the strength of the geometrical laws, to travel n-times (for an n-cornered workpiece) through the generating curve 3. The cinematics of these motions are known. In Fig. 2 the perpendicular to the curve 11. is displaced upwards by the length of the great axis of the generating curve 3. In Fig. 1 the center of the grinding wheel coincides with the left-hand apex of the generating curve, and in Fig. 3 with the right-hand apex. The shape of the generating curve results, with mathematical precision, from the shape of the non-circular profile which is to be produced. If said shape is selected so that, with profiles having an odd number of corners, the same measuring distance is produced in any position, i. e. that a body of equal thickness is attained-which is highly advantageous in view of the possibility of employing usual calibres (grooves) in outer profileson basis of the mathematical laws the generating curve is formed to be an ellipse, the ratio of the axes of which corresponds to the number of corners. This relation is the basis for the design of the controlling gear according to Fig. 4.

In said figure the control eccentric is designated by numeral 4, the control movement being derived from said eccentric. In a manner to be explained hereinafter, this eccentric is continuously adjustable from the eccentricity zero (circular working) up to the maximum eccentricity. In this embodiment the tools used are, on the left-hand side, an outer-grinding wheel 5 for working the outer profile 6, and on the righthand side an inner-grinding wheel 1 for working the inner profile 8. The motion of the tool required for realizing the profile shape is composed of two components, the one coinciding with the feeding direction of the tool (i. e. horizontal according to Fig. 4), and the other to the direction perpendicular to the feeding direction (1. e. vertical according to Fig. 4). The component acting in the feeding direction is, by the control eccentric and the tappets 9 and 9a, directly transmitted on to the tool support, whereas the component acting in the perpendicular direction thereto is transmitted indirectly by way of the tappets l0 and Illa. located one behind the other in the drawing, the double-armed levers l l and I la, and the tappets l2 and I2a. All tappets are guided in the tool-block. The ratio of transmission of the levers l l and I la is adjustable according to the number of corners of the profile to be produced by means of stuck-in bolts I3 and I3a, located between the levers II and Ila, and the lever supports [4 and Ma. The ratio of transmission amounts to 1:11., whereby n is the number of corners of the profile to be produced.

The suspension of the grinding wheel support is taken care of by the oscillating levers l5 and 15a, supported in the tool-block, as well as by the links I6 and Hill. This mode of suspension assures a guidage parallel to the axis without, however, reducing the mobility in the direction perpendicular to the grinding spindle axis, the traction springs I1 and lla warranting a positive operative connection of the tool support with the control eccentric 4.

The drive of the grinding wheels 5 and I of said embodiment. is derived from the motor [8, fixed to the tool-block and consequently not partaking in the oscillation, two V-shaped belt drives l9 and 19a, as well as 20 and 20a taking care of the transmission of the energy. The mean belt pulley support is lodged in the guide so that the belt length is not altered by the control motions of the tool.

Fig. 5 shows the adjustable control eccentric (4 in Fig. 4). On the eccentric 2|, having the eccentricity e a second eccentric 22, having the same eccentricity, is rotatably arranged. By a relative rotation of the two eccentrics, one in respect to the other, the amplitude of the efficient eccentricity can be adjusted continuously from zero to 2e. This is effected by operating the hand wheel 23 which acts on the gear wheels 24, 25, 2B and the inner toothing 21. When the eccentricity desired is attained, the position of the two eccentrics is fixed in regard to each other by means of the clamping sleeve 28 and the clamping screw 29. By way of the ball bearings 30, 30a, 3| and 31a, arranged on the eccentric 22, the movement of the eccentric is transmitted to the tappets 9, 9a, l0 and [0a (Fig. 4). The drive of the eccentric shaft supported in the tool-block is effected by the control motor 32, acting by way of the gear wheels 33. By altering the ratio of transmission between 32 and 33, the number of revolutions of the eccentric shaft is adapted to the number of corners of the profile to be ground.

The Figs. 6 and 7 showthe support and the drive for a milling device preferably intended for the preliminary workon outer profiles which this case infinite, no control motion is necessary in the perpendicular to the feeding direction which feature is of great importance for the precision of the tool guidage in view of the-relatively high cutting pressure occuring in milling. In other terms, the tool only carries out: an oscillating motion in the feeding direction which is either derived directly from the tappet 9a. (Fig. 4) or as represented in the embodiment under consideration from a bushing 34, rotatably arranged on the bearing sleeve of the inner grinding spindle I. The hollow shaft 36, rotatably journalled in an additional casing 35, rigidly connected to the tool-block, is actuated by the motor l8 (Fig. 4) by way of a belt drive (not shown) as well as by a worm 31 and a wormgear wheel 38. In said hollow shaft the milling spindle 39 is longitudinally shiftable, but is rotatably coupled with said shaft. On the one end the milling spindle 39 shows a conical bore for 'the shank of the milling cutter 42, whilst at the other end an arrangement is provided for the bearing of a rotatable mushroom-shaped part 40 which rests on the bushing 34 of the inner grinding device 1 or directly on the tappet 9a (Fig. 4). The spring 4| assures a permanent and operative connection between the milling cutter 42 and the element from which the oscillating motion is derived.

Instead of or in addition tothe milling device it is possible to install a turning device for inner and outer profile (not shown in the drawing).

The Figs. 8 and 9 are a frontal view and an end view of the machine-tool as a whole. Numeral 43 designates the machine base on which the carriage 44, supporting the headstock 45 and the tailstock 46, is so arranged as to be shiftable in the longitudinal direction. The tool-block 41, located behind, is shiftable in the feeding direc tion of the tools, besides being rotatable about a vertical axis 48 in such a manner that the various tools such as the outer-grinding wheel 5 in Fig. 8, the outer-grinding wheel 5 and the milling cutter 42 in Fig. 9 can be moved into their operating position.

Fig. is an overall plan of the machine-tool, whereby the tool-block 41 is turned through 180 in respect to the positions shown in the Figs. 8 and 9, whereas the inner-grinding wheel I occupies its working position. The Figs. 11 and 12 also show the whole machine seen from above, and by way of an end view, but in its case with the milling head 42 in its operating position. Just as in the Figs. 8 and 9 the numeral 43 refers to the machine base, 44 to the carriage, 45 and 46 to the headstock and the tailstock, and 4'! to the tool-block. In these three figures the outergrinding wheel 5 occupies a position outside of the tool-block turned away from the workpiece.

From the overall views of the Figs. 8-12 it can be gathered that on basis of the design according to the invention it is possible to provide the same tool-block with the necessary devices for preliminary work (milling or turning), as well as for outerand inner-grinding, and that the various tools can be optionally moved into their working position by turning and longitudinally shifting said tool-block.

6 WhatI claimisz' v, f I 1. A machine tool comprising a rotatable work supporaa tool, arotatable support for-said tool mounted to move parallel to its axis of'rotation, a

single rotating cam means having a continuous single surface, and-two cam follower means engaging different portions of said surface and being guided for movementindifferent directions, said follower means'eng'ag-ing said tool support for moving it parallel to] its axis of rotation in a direction resulting from the combination of the movements of said follower-means.

2. A machine tool as defined in claim 1, one of said cam. follower means being formed by a tappet' rod having one end engaging said cam and another end engaging said tool support, and the other follower means being composed of two tappet rods and atwo arm lever, one end of one tappet rod engaging said cam and the other end engaging one arm of said lever, one end of the other tappet rod. engaging the other arm of said lever and its other end engaging said tool holder.

3. A machine tool as set forth in claim 2, the two tappet rods engaging said lever being longtitudinally movably supported parallel to one another and substantially at a right angle to the tappet rod engaging said cam and said tool holder.

4. A machine tool as-set forth in claim 2,;comprising resilient means pressing said tool holder to the two tappet rods by which i-tis engaged.

5. A machine tool asset-forth inclaim 2, said lever having a displaceable fulcrum for chang ing its leverage. 1 u H I 6. A machine tool having a rotatable work support, a tool, a rotatable'support for said tool mounted to move-parallel to its axis of rotation, an eccentric, and two motion transmitting. means actuated by said eccentric andibeingguided to move in different directions and individually engaging said tool support for transmitting'the movement of said eccentric thereto and moving it parallel to its axis of rotation in a direction resulting from the combination of the movements of said two transmitting means.

7. A machine tool as defined in claim 6, said eccentric being composed of two eccentrics disposed within one another.

8. A machine tool as set forth in claim '7, the eccentricity of-both 'eccentri'os'being the same.

9. A machine tool as set forth in claim 7, comprising means for rotating said eccentrics relative to one another for changing their composite eccentricity.

10. A machine tool-as set forth in claim 7, comprising friction meansjfor fixing the relative position of said eccentrics. r I V v 11.A machine tool for shaping the surface of a workpiece comprising, in combination, a rotatable work support, a tool, a rotatable support for said tool movable parallel to its axis of rotation, a rotatable cam means, and two motion transmitting means actuated by said cam means and guided to move in different directions and individually movably connected with said tool support for transmitting the movement of said cam means thereto and moving it parallel to its axis of rotation in a direction resulting from the combination of the movements of the two transmitting means. one of said transmitting means comprising variable transmitting means for changing the extent of motion imparted to the tool support by the last mentioned transmitting means relative to the extent to which it is actuated by said cam means.

12. A machine tool for shaping the surface of a work piece comprising, in combination; a rotatablework support, a tool, va rotatable support for said tool movable parallel to its axis of rotation, a rotatable cam means, two motion transmitting means actuated by said-cam means and guided to move in different directions and individually movably connected with said tool support for transmitting the movement of said cam means theretoand moving it parallel to its axis of rotation in a direction resulting from the combination of themovements of the two transmitting means, a stationary motor, a pulley swingably linked to said motor, means swingably suspending said work support from said pulley, and flexible means connecting said motor with said pulley and said pulley with said work support for rotating the latter by said motor.

13. A machine tool for shaping work pieces internally and externally comprising, in combination, a rotatable work support, two. tools, a rotatable support for each tool, said supports being individually movable parallel to their rotation axes, a rotatable cam means, a motion transmitting mechanism for each tool support, each mechanism comprising two motion transmitting means actuated by said cam means and guided to move in different directions and individually movably connected with one of said tool supports for transmitting the movement of said cam means thereto and moving it parallel to its axis of rotation in a direction resulting from the combination of the movements of the two transmitting means. I

14. A machine tool as defined in claim 13, comprising a machine bed supporting said work support and a turret rotatably supported by said bed and supporting said tool supports, said cam means, and said motion transmitting mechanisms. r

15. A machine for preliminarily milling and finally grinding the surface of a work piece comprising, in combination, a rotatable work support, a grinding tool, a rotatable support for said grinding tool movable parallel to its axis of rotation, a rotatable cam means, two motion transmitting means actuated by said cam means and guided to move in different directions and individually movably connected with said tool support for transmitting the movement of said cam means thereto and moving it parallel to its axis of rotation in a direction resulting from the combination of the movements of the two transmitting means, a milling tool, and a rotatable and axially movable support'for said milling tool engaged by said grinding tool support for axial movement toward and from the work in accordance with the lateral compor Number nent of the movement of the grinding tool support. v

16. A machine for preliminarily milling and finally grinding the surface of a work piece comprising, in combination, a rotatable work support, a grinding tool, a rotatable support therefor movable parallel to its axis of, rotation, a rotatable cam means, two motion transmitting means actuated by said cam means and guided to move in different directions and individually movably connected with said tool support for transmitting the movement of said cam means thereto and moving it parallel to its axis of rotation in a direction resulting from the combination of the movements of the two transmitting means, a milling tool, a rotatable and axially movable support therefor, and motion transmitting means actuated by said cam means and movably connected with said milling tool support for moving it in axial direction.

17. A machine tool for shaping the surface of a work piece comprising, in combination, a rotatable work support, a tool, a rotatable support for said tool movable parallel to its axis of rotation, a rotatable cam means, two motion transmitting means actuated by said cam means and guided to move in diiferent directions and individually movably connected with said tool support for transmitting the movement of said cam means thereto and moving it parallel to its axis of rotation in a direction resulting from the combination of the movements of the two transmitting means, a normally stationary turret, a motor fixed to said turret to rotate said cam means, a second motor fixed to said turret, and flexible means connecting said second motor and said tool support for rotating it.

ROBERT MUSYL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Grohmann et a1. Oct. 11, 1898 Stubbs Feb. 13, 1940 Wildhaber Aug. 6, 1940 Hinkley et a1 July 14, 1942 Horton May 30, 1944 Bryant June 12, 1945 Green Jan. 28, 1947 Brown Nov. 2, 1948 FOREIGN PATENTS Country Date Great Britain Oct. 9, 1934 Number 

